Improvement in friction-brakes for machinery



JOHN C. CLAPP. 4 Improved Brake for Printing Press.

Patented August.15, 1871.

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NITE TATES JOHN G. OLAPP, OF BOSTON, MASSACHUSETTS.

IMPROVEMENT IN FRICTION-BRAKES FOR MACHINERY.

Specification forming part of Letters Patent No. 118,107, dated August 15, 1871.

To all whom it may concern:

Be it known that I, JOHN G. CLAPP, of Boston, in the county of Suffolk and State of Massachusetts, have invented certain Improvements in Brakes for Printing-Presses, of which the following is a specification:

My invention consists in the application of friction to the two sides of the periphery or rim of the fly-wheel of a printing-press at that point which is horizontal or nearly horizontal with the center of the wheel, and at which the motion of the wheel is downward, for the purpose of stopping or checking the motion of the press.

Figure 1 is a front elevation of a machine embodying my invention. Fig. 2 is a side elevation of the same, showing its position in respect to the fiy-wheel of the press, and the mode in which it is operated by a lever.

A A are two perpendicular arms, vibrating on the two pins 0 c, which pass through and are supported by the two sides of the frame B B B B. B B B B is a fixed frame, firmly secured to the foot-piece E, having its two sides as represented in Fig. 1, and its two ends as in Fig. 2, its object being to keep the two arms A A in their proper position. E is the foot-piece, by which the whole is secured to the floor. C O G O is a movable frame, having its two sides as shown in Fig. 1 and its two ends as in Fig. 2. It is provided with the two beveled projections c c, which act upon the opposite projections 11 b in the arms AA. It is also provided with an opening, h, at each of the two ends, to admit the ends of the rod j which passes through the spiral spring S and arms A A, as shown in Fig. 2. 1t is an iron rod hung upon the lower portion of the frame 0 O O O, and connected at its lower extremity with the end of the lever used for operating the brake. S is a spiral spring which surrounds the rodj, and which forces the two arms A A back into position when the pressure upon them is removed. F is a fulcrum for the lever used to operate the brake.

Like parts are represented by like characters in the drawing.

It will be seen that when force is applied to the lever by the foot of the operator the rod R and frame 0 C O O are raised, and, the two projections c 0 being forced against the projections I) b, the upper extremities of the arms A A are made to grasp the rim of the wheel in the manner of a use.

My invention is designed particularly for job printing-presses,in the brakes generally used up on which the friction upon the wheel is given from beneath and the entire pressure thus comes on the end of the shaft holding the Wheel, which.

shaft, being often made of cast-iron, and unsupported by any bearin g for some distance from its extremity, is thus subject to an undue strain whenever the brake is used. By my invention this difficulty is entirely obviated, and the pressure caused by the friction upon the wheel comes in a great measure directly upon the floor. Another advantage of my invention consists in the additional length which, by its use, is allowed for the lever which operates it,

I claim as my invention- 1. The application of friction to that portion of the fly-wheel of a printing-press hereinbefore described, for the purpose as set forth, by means of arms A A, or other arms acting upon the wheel in the manner of a vise.

2. The combination of the fixed frame 13 B B B, the movable frame 0 C G O, and the rod R, acting in the manner and for the purpose described.

WVitnesses: JOHN G. GLAPP.

F. W. GRANTHAN, W. M. Bnnws'rnn. 

